Spare tires for large trucks are heavy and bulky and are usually accommodated below, and secured against, the vehicle body or against a structure carried by elements of the vehicle chassis. Because of their weight and size, vehicle spare tires can rarely be lowered to the ground, nor raised for storage, by hand. For this reason, heavy trucks are provided with hoisting devices, such as hand-operated winches, by means of which these tires are cranked down for use or cranked up for storage.
One difficulty encountered with these hoisting devices resides in the fact that, because of the need for compactness and the cramped location of the spare tires, it was rarely possible to ensure coaxiality for the drive shaft of the hoisting device and the crank handle whereby this shaft is to be rotated to lower or raise the spare tire. As a result, all sorts of connectors, universal joints, etc., had to be resorted to, adding bulky items to the driver's toolbox.